Blocks of cocaine worth $2 million were confiscated by authorities pursuing a Western Pennsylvania drug ring last November.

Department of Justice Western District of Pennsylvania

Pittsburgh played host to one of the largest cocaine rings in Western Pennsylvania history, according to U.S. Attorney Scott Brady, who served 39 indictments related to the case on Wednesday. The organization spread through Pittsburgh, Atlanta and Los Angeles, with the cocaine sourced from Mexico.

"By taking down an entire multi-state organization at once, the impact on our region is immediately felt," Brady said.

Authorities seized $2 million worth of cocaine in November, along with one kilogram of heroin, 85 pounds of marijuana, 11 firearms and over $1 million in cash. Thirty-seven of the 39 defendants have since been arrested and are in custody, including two Pittsburgh-area ringleaders, brothers Jamie and Deaubre Lightfoot, who police say were supplied by Don Juan Mendoza of Georgia

The case signals an uptick in cocaine use in the Allegheny, Fayette, Greene, Washington and Westmoreland county region, Brady said, which he said he believes is due to the increased attention on opioids by federal and local authorities.

"We hear anecdotally, and see in our investigations, that people are aware that we are charging federal mandatories [sentences] aggressively and that they will be held accountable," he said. "So [cocaine] is kind of filling that void."

Brady said an increasing amount of drug overdoses are due to a combination of cocaine and fentanyl.

There's evidence to suggest that cocaine is more addictive for adolescents than adults. Scientists believe that at least part of this has to do with biological mechanisms in the brain, but they're not sure exactly what those mechanisms are.

A special sensor being developed at the University of Pittsburgh could help give them a better understanding.

Gov. Tom Wolf on Monday asked the Legislature to pass a measure expanding background checks on firearms in Pennsylvania and end an exception for private sales of shotguns, sporting rifles and semi-automatic rifles, known as the "gun show" loophole.

The Democratic governor appeared at a news conference in his Capitol office with officials from the Pennsylvania State Police supporting his call for action as lawmakers consider firearms-related measures in the wake of February's Parkland, Florida, high school shooting that killed 17 people.